Improvement in steam engines



@with taies atrrtt4 @Hita JOHN L. LAY, OF BUFFALO, NEW. YORK, ASSIGNOR- TO I-IIMSELF` .NDv

H. O. PERRY, OF SAME PLACE.

Letters Patent No. 66,975, dated Jar-ly 23,1867- I IMPROVEMENT IN STEAM ENGINES.

@Le Stimuli tarnish tu iu tlgcsr hitters-@rient mit mating putt at tige same TO ALL WHOM IT MAY CONGE-RN:

Be it known thatI, JOHN L. LAY, of the city of Buffalo, in the county of- Erie, and State of New York, have invented certain new and useful Improvements in Vertical Compound Engines; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, making part of this specification, in whichl l Figure 1 is a central vertical section of my improved engine.

Figure 2 is a front elevation of the same with portions of the valve-chest brolenaway to show the ports.

lFigure 3 is a view, partly in'section, of the valve detached. l l

Like letters designate corresponding parts in all the figures.

The design of my invention is the production of a compound engine, consisting of a high and a lowpressure cylinder, of a compact form, suitable for vessels propelled by moans of a screw.

The invention consists' in the special arrangementof the cylinders concentrically, one within. `the other, with their pistons connected by three rods attached to a common cross-head below the cylinders; and also in the construction and arrangement of a single oscillating valve for operating both cylinders, all as hereinafter fully set forth.

In the drawings, A B represent two cylinders, the latter arranged eoncentrically within the former, and both closed at their ends by the same heads C D. E is the piston of the inner, and F the annular pistonv of the outer cylinder, the former attached to the ends of a rod,.G, and the latter to two rods, H I, all extending downward through the bottom head D, where they are fastened to the same cross-head J, as represented. From this crosshead a'rod connects with the crank of the screw-shaft. The steam from the boiler enters the smaller or high-pressure cylinder, and is cut off at any desired point, effecting a certain amount of expansion in that cylinder, from whence it is exhausted into the larger cylinder and-expands the whole length of the stroke., and thereby is expanded in both cylinders.

K The advantages of this arrangement of. the cylinders are: Great couipactness and power, as they together occupy no more space than a single one would, while their combined power is much greater. It also brings the centre of. gravity of the engine and connecting machinery much lower than it would be were they arranged one above the other. It is more simple, cheaper, and weighs less than any other arrangement of the same newer with which I am acquainted.

K represents the valvechest; L an oscillating valve, and m n op the ports, of which m n are the steam@ ports to the high-pressure, and opthe ports to the low-pressure-cylinder; and g is the exhaust-chamber, which opens into thc valve-chamberr, from whence the exhaust steam escapes through the trunnion s into the externa-l air'or condenser, as required. The port mA opens into the top of the high-pressure cylinder through the headl 0,: while the port n communicates in like manner, as shown, with the bottom of same. The port o leads to the top ofthe low-pressure cylinder A, opening into the same through the side, while p connects in like manner with the bottom of the cylinder, the former connecting with the port n and the latter with m, while the valve is respectively at its cxtreme throws, when they operate as an exhaust from the high-pressure cylinder and conduct the-steam to the lower-.pressure cylinder. The steam exhausts from thecylinder A alternately through the ports op into the chamber g, whence it escapes .through the valves, as before described. The valve L terrninates at the end in a hollow trunnion, s, and at the other in a spindle, t, by which it is connected to the eccentric that gives it the required oscillating motion. The face of the valve forms an are, with the axis at its centre, with which the valve-seat corresponds. It is provided with two-cavities, u it, and a recess, n, at the centre, leading into the valve-chamber r. The face of the valve alternately covers-m and n at the extreme throws; the valve being represented in fig. l as closing port m, while steam is admitted through it to the bottom of cylinder B, and at the same timedexhaustcd from thevupper end of the same through port m, which now communicates with the port p that conducts the exhaust steam to the lower end ofthe low-pressure cylinder A., (as shown by the arrows,) port o connecting with the upper en d of the cylinder 5A, aiording apassage for the exhausted steam therefrom into the chamber y, into which it now opens; from thence it escapes through recess e into'the valve-chamber 1, and thence through the trunnion, as above described. 'When the valve is at the other extreme it is evident that the portn will be closed and m opened, causing simply a reverse movement of the steam through the various ports, the portp now opening into the chamber g instead of the port o.

'lhe advantages of this part of my invention are, first, dispensing with theuse of one or more valves and the necessary machinery required for operating them, as my simple valve performs the functions of two or more as they are ordinarily'constructed; second, the great saving in expense and in the space required for lthe valve and actuating machinery, as Well as for the engine itself; third, the diminished Weight ofthe same, which', on the vessels for which this engine is designed, is ot' considerable importance. l

1. I claim the arrangementof the liiglrpressure cylinder B concentrieally within the low-pressure cylinder A, when. both are closed by the same heads C D, and the pistons actuate rods attachedtothe same cross-head below the cylinders.

2. I also claim the valve L provided with the cavities u u, recess '11, valve-chamber r, and hollow trunnion s, in combination with the ports m n op and chamber g, for operating the two cylinders of a high and 10W-n pressure engine, substantially as set forth. v v

3. The valve, constructed as described, in combination withthe concentric cylinders A and B of a high or 10W-Pressure englll.

In witness whereof I have hereunto signed my name in the prescnce'of two subscribing witnesses.

JOHN L. LAY.

Witnesses:

JAY HYATT, J. R. DRAKE. 

